Power-up

MTG Mechanic

Each power-up ability is an activated ability that can be activated only once. You'll put one or more +1/+1 counters on the creature. These serve as a handy reminder that you activated the power-up ability. There may also be other effects, some of them quite devastating. If the creature enters and you activate the power-up ability all in the same turn, you get a discount on the power-up activation. That activation cost will be reduced by the creature's mana cost.